Crankshaft, Rod bearing wear. How much is too much?

[scott-superman]

G'Day All,

This is the continuation of my post about getting an oil pan off of a 1987 325i. Got it off and repaired oil pan, but a couple of the crank bearings looked a little dry so I pulled them off. They obviously got a little hot by being starved for oil after the oil pan was punctured. Some of the babbit material is worn off of the bearings on one and more on another. The crank journals look and feel OK. The vehicle has 153,000 miles on it. I don't know how these compare to any other vehicle with this many miles that didn't starve for oil???

Should I put them back and see how the car runs and let it ride or remove the main and rod bearings, replace them, and have the crank turned?

Thanks All!

 

[vlad]

It would kinda depend on how much work you would like to do. Like if the bearings fail, would you be out too much time to tear it all back down again?

Personally, as critical as BMWs are on rod bearings and the lower end, I would take it to a shop, have them mic it, and let them make recommendations on whether it is polishable or it it needs turning.

 

[///M SPEED]

vlad, did your M3 need the connector rod bearings done like mine? Did it fall under the production period of the Service Action? I just recently had mine done. The producton dates are from 02/02 to 03/03 I believe.

 

[scott-superman]

It would kinda depend on how much work you would like to do. Like if the bearings fail, would you be out too much time to tear it all back down again?

Personally, as critical as BMWs are on rod bearings and the lower end, I would take it to a shop, have them mic it, and let them make recommendations on whether it is polishable or it it needs turning.

Hello,

Thanks for insight. I am going to show the two main bearings to my mechanic today and see what he thinks. I know they are not ideal, but what is about a 17 year old original car? I also need it to drive for a little while to do a little work on my diesel truck to get it back running on used vegetable oil. Buying diesel for $2 per gallon sucks when you can drive for free!

G'Day

 

[mjbst111]

I would just change them out. All of them. You are talking about just the lower bearings right? It's so easy to do, why not just replace them. I wouldn't bother with a mic or mechanic, you have the pan off.... Thats the hardest part.

 

[geneo]

as long as it doesent look like any of them spun i would just replace them mains and rods while the pan is off

 

[scott-superman]

Hello vlad, mjbst11 and geneo,

I think that is the route I am taking. Am going to check all of them to make sure that none of them spun and then, if not, replace the rod and main bearings. Will make sure journals look ok too. Thanks for the input!

Anyone know a good source for the bearings?